198 PROFESSOR LETTS AND N. COLLIE ON THE 
They were then dried at 120°, but did not lose weight, so they were at once 
submitted to an elementary analysis. 
0:4234 eave 1:230 CO, = 79:2 percent. carbon. 
04234 ,, 02589 H,O = 68 x hydrogen. 
These results, so different from those required by the hydrate, we could not 
explain, and therefore again repeated the experiment with the acid -sulphate 
and caustic baryta as far as possible under the same conditions as before—with 
larger quantities, however—but with exactly the same result. No body soluble 
in water was produced, but an insoluble body was precipitated with the 
sulphate of barium, soluble, however, as we had before noticed, in alcohol, and 
having on recrystallisation the same melting point (210-212° C.). Its analysis 
gave numbers agreeing with those we had previously obtained. 
05958 gave 1°7221 CO, = 78°8 per cent. carbon. 
05958 , 03636 HO = 68 hydrogen. 
Obviously then two distinct substances are formed by the action of caustic 
baryta on the acid sulphate, under conditions which vary only slightly from 
each other. 
On consideration, but one explanation appeared probable, viz., that the base 
suffered decomposition ; and the only change which appeared at all likely for 
it to undergo was a loss of hydrogen and benzyl, and, consequently, the forma- 
tion of oxide of tribenzyl-phosphine. This change would be analogous to the 
decomposition which HormMann observed on heating the hydrate of tetrethyl- 
phosphonium, which he found to decompose with formation of ethane and 
oxide of triethyl-phosphine, 
(Cat, P(OH) =(CoH.),PO+CLH. - 
Similarly, hydrate of tetrabenzyl-phosphonium might split up into toluol 
and the phosphine oxide, 
(C;H,),P(OH)=(C,;H,);PO + C,H . 
On comparing the percentages of hydrogen and carbon required for the 
oxide of tribenzyl-phosphine, with the results of our analyses of the body soluble 
in alcohol, we found that they corresponded. 
Obtained. Calculated for 
i, IL (C;H,),PO. 
Carbon, ; . 79°2 : ; 788 78°75 
Hydrogen, . A 68 : : 68 5 : 6°56 
It only remained to ascertain whether toluol was produced in the reaction. 
7 grms. of the acid sulphate were placed in a distilling flask, and about the same 
